Choose a mobile signal booster rated for the indoor floor area you actually need covered, with some margin for walls and roofing, and check that the signal outside is good enough to fill that area. For most Australian houses that means a kit rated around 300 to 500 square metres; larger homes, offices and sheds may need more.

The rated area on the box is a best case. Here is how to measure your space and pick the right size first time.

How do you measure the area you need to cover?

Measure the internal floor area of the rooms where you use your phone, not the size of the block. A floor plan from your purchase or rental documents often lists it. If not, multiply the length by the width of each room and add them up. For a two-storey home, add both floors together.

Then decide which rooms really matter. Many people only need strong signal in the living area, kitchen, home office and main bedroom. Covering those well with a smaller kit often beats covering every corner weakly with a larger one.

Why is the rated area a best case?

A booster can only spread as much signal as it receives. The rated coverage assumes a reasonable signal outside and an open layout. Two things shrink it in real homes:

  • Weaker outside signal. If the outdoor antenna only picks up one bar, the boosted signal indoors will reach a smaller area than the rating.
  • Building materials. Double brick, concrete slabs, metal roofing, foil insulation and tinted or low-E glass all absorb signal between rooms.

As a rule of thumb, if the outside signal is weak or the house has many solid internal walls, choose a kit rated for around one and a half times your floor area.

Which size suits which home?

  • Unit, apartment or small house up to about 150 sqm: a 300 sqm kit such as the 4G/5G Signal Booster 300 sqm leaves good headroom.
  • Typical family home of 150 to 300 sqm: a 500 sqm kit such as the 4G/5G Signal Booster 500 sqm covers most layouts.
  • Large or two-storey homes, small offices and shops: consider a higher-powered universal kit such as the Power Max Universal 5G Signal Booster, or a kit with extra indoor antennas.
  • Farm sheds, warehouses and separate buildings: each building far apart usually needs its own kit, or a high-power system with antennas run to each area.

Is a bigger booster always better?

Not always. A larger kit costs more and only helps if there is enough signal outside to fill the space. In a small home with a strong outside signal, a big amplifier adds little. In a large home with a weak signal, a bigger kit with a directional outdoor antenna is often worth it.

Placement matters as much as size. Mount the outdoor antenna where the signal is strongest, keep it well apart from the indoor antenna, and put the indoor antenna centrally or in the room you use most. Our installation guide covers this step by step.

What else affects the choice besides size?

Size is only one part. The kit must also cover the frequency bands your network uses at your address. If everyone uses the same network, choose a kit for Telstra, Optus or Vodafone. If people use different networks, a universal kit such as the Home Pro Universal 4G/5G covers them together.

And check there is a usable signal outside. One or two steady bars on the roof line or in the yard is usually enough. If there is no signal anywhere outside, no size of booster will help.

What mistakes do people make when sizing a booster?

The most common mistake is measuring the whole block instead of the indoor area that needs signal. A booster covers the inside of buildings, so sheds, decks and the yard do not count unless you want signal there too. The second mistake is ignoring construction: brick, concrete, metal roofs and foil insulation all shrink the real coverage of an indoor antenna, so a home built with them may need the next size up or an extra indoor antenna.

The third is buying a bigger kit to make up for a weak outside signal. A larger booster cannot create signal that is not there; a better outdoor antenna, mounted higher and aimed at the tower, usually helps more. If you are between two sizes, send us your floor plan and we will tell you which one fits.

How can we help you choose?

Send us your floor plan, address and network through our floor plan analysis page and we will suggest the size and kit. You can also read our guide on how to choose the right booster. Delivery is free in 5 to 7 working days, and you can return a kit within 30 days.

Frequently asked questions

How many square metres does a mobile signal booster cover?

It depends on the kit and the signal outside. Home kits are commonly rated from 300 to 500 sqm, and larger systems cover more.

Should I measure the house or the whole block?

Measure the indoor floor area you want covered, not the block.

Does a two-storey house need a bigger booster?

Often yes, because floors and slabs absorb signal. Add both floors together and allow extra margin.

Can one booster cover the house and a shed?

Only if they are close and within the kit’s range. Separate buildings far apart usually need their own kit.

Send us your floor plan and network, and we will tell you which size fits. Get a free floor plan analysis